Paul's Bizarre Worm Bazaar

A Selection of Fine Worms

Paul's home page (under construction)

Published Papers (under construction)

Here are my collected works, with notes on subsequent developments, changes
of opinion or blatant errors. The 3-digit numbers preceding each reference
are registration numbers in the reprint collection of the Institute of
Zoology at the University of Ghent. If the 3-digit number of a given paper
is highlighted, then reprints of that paper are (at least to my knowledge)
still available and can be requested from the Librarian
of the Institute.

(678) SHAHINA, F. & DE LEY, P. (1997). Two
new species of Cephalobidae from Valle de la Luna, Argentina and observations
on the genera Acrobeles and Nothacrobeles (Nematoda: Rhabditida).
Fundamental and Applied Nematology 20: 329-347.

(none) DE LEY, P. (1997). The current state of affairs in identification
and diagnosis of the genera of the family Cephalobidae (Nematoda: Rhabditida).
Mededelingen Faculteit Landbouwkundige en Toegepaste Biologische Wetenschappen,
62: 657-673.

Where to request reprints:

474 - Comments on the description of Metacrobeles:

- Contrary to the text, males of Metacrobeles have three
pairs of genital papillae on the tail tip (one laterosubdorsal, one lateral
and one laterosubventral pair) just like all other Cephalobidae. I checked
paratypes when I began to realise that many published descriptions contain
incorrect numbers of male genital papillae. Apparently, all males
of Cephalobidae have five pairs of genital papillae on the tail, two or
three pairs preanally, and a tiny single midventral papilla on the just
anterior to the cloacal aperture.

- The number of stoma parts visible with light microscope in Metacrobeles
(6) is not at all unusual within Cephalobidae - it only seemed so at the
time, compared to previous drawings and descriptions. Some of my later
papers (547, 616 and 625) returned to this issue and reinterpreted the
"typical" stoma structure of cephalobids. As a result, Metacrobeles
is only distinctive in the posterior vulva position and extreme spicule
length, two characters that are functionally linked. I no longer think
it merits special status among cephalobid genera, not even as a separate
subfamily.

498 - Comments on the description of Stegelletina
doorsselaeri:

- My first encounter with Cervidellus-like species, and the beginning
of a long struggle with some of the cutest and most taxonomically maltreated
species of cephalobids.At the time, we still adhered to Andrássy's
(1984) diagnosis of Stegelletina as containing species with longitudinal
lines, bifurcate probolae and pointed tail. By now, Stegelletina has
been sunk (598) and resurrected (Boström & De Ley, 1996) again
as a genus with species having primary axils with single guard process,
bifurcate probolae and mucronate tail. S. doorsselaeri is currently
classified as Cervidellus doorsselaeri (De Clerck & De Ley,
1990) Boström & De Ley, 1996 ... until the next twist of the tale.

- S. capraeola is close to S. doorsselaeri and currently
classified as Cervidellus capraeolus. See comments above for S.
doorsselaeri.

- The beginning of another tortuous story, where I have been fooled
at every turn by the one cephalobid species I love to hate: Acrobeloides
bodenheimeri. In this first of many slip-ups, we described a bodenheimeri-like
species from Senegal as new species C. camberenensis, because we
accepted the species diagnosis of A. bodenheimeri in Andrássy's
(1984). One year later, when I finally had the good sense of requesting
type material, it turned out that A. bodenheimeri has five lateral
lines and a long postvulval sac, just like C. camberenensis. So,
in (572) we sunk C. camberenensis while redescribing A. bodenheimeri.

Two years later I met Marie-Anne Félix when she was presenting
a poster on gonad development in Cephalobidae. She told me she had a left-handed
species of Cephalobidae (Félix et al., 1996), and when I
received material for identification it proved to be ... A. bodenheimeri
- after checking the type material AGAIN and comparing with Steiner's drawings
(which clearly depict left-handed male and female reproductive systems).
By contrast, the type material of C. camberenensis is right-handed,
and a right-handed strain in culture from Senegal does not interbreed with
cultured strains of A. bodenheimeri. Conclusion: C. camberenensis
IS valid and provisionally placed in Acrobeloides with its "twin"
A. bodenheimeri (the implications of these species to genus
diagnosis are even more worrying, and at the moment there is no coherent
solution to their classification). A paper on this new turn is in preparation.

523 - Comments on 3 Rhabditida from Fernandina:

A premature paper if ever there was one: it got me into another quagmire
called Panagrocephalus aka Pseudacrobeles, two genera that
were classified in separate subfamilies by Andrássy (1984) but are
actually identical (582, 583) and contain the taxonomic "seeds of destruction"
for the much more widely reported genera Heterocephalobus and Eucephalobus.
In turn, Pseudacrobeles is only distinguishable from Cephalobus
by the length of the lateral field on the tail - a mere technicality.
But in addition to genus complications, Pseudacrobeles also
looms large as one of the most fluid collections of nominal species, and
the type species is very appropriately called P. variabilis.

With this first paper on nematodes from the Galápagos, I made
the mistake of writing up a description of "new subspecies" Panagrocephalus
anadelphus impervius before I had gotten through all samples from the
other islands visited. Three years later, after a very exhausting detour
through numerous populations from the Galápagos and other tropical
locations, it turned out that almost everything in this trinomen was wrong
- the species is now classified as Pseudacrobeles [variabilis] impervius,
and it remains very much to be seen whether separate species status within
putative superspecies P. [variabilis] is at all meaningful (let
alone correct).